check the fuse first!
There are two flashers, one for the hazards and one for the signals.
The 1990 VW Jetta turn signals will not work when the ground wire is broken or corroded. The turn signals may need the lightbulb's replaced.
I replace my flasher fuse.Now they light up but won't blink.
Multifunction switch is bad.
Most likely a bad turn signal flasher or blown fuse
have you tryed all the fuses then check if the bulbs are good
If the turn signal bulbs light but will not flash, the flasher relay is defective, replace it.
replace flaser can in fuse box
Could be the flasher unit.
Your problem is most likely the turn signal relay im having a problem similar to yours but when my signals wont work neither do my hazards
The turn signals and hazards are on separate relays. You need to replace the signal relay. If that doesn't do the trick, look into your turn signal switch.
If the turn signal lights come on but will not flash you have a defective flasher relay. Replace the relay.